During the show, the Tennessee native performed the song "The Courage to Love," which was written by Brooks himself after some nudging from of AGT judge Simon Cowell.

It was Cowell who put the initial request out to Brooks on the the first night of this season's AGT Semi-Finals. Shortly afterward, Brooks addressed the request on an episode of his weekly livestream, Inside Studio G, saying that he would definitely consider it. On Monday, Brooks and Ketterer appeared together to confirm that a song had been finished.

Garth Brooks Goes All Out! Watch His Most Unforgettable Moments

And while the melancholy song of hope and determination left folks in the crowd completely touched by its sincerity, Ketterer still ended up coming in fifth place on the show, as magician Shin Lim came home with the fan-voted top prize. But it's far from the end of the story for Ketterer and Brooks — the legend has invited the budding star to perform with him during his upcoming show at Notre Dame on Oct. 20.

Ketterer also has another big fan in his back pocket: Cowell himself, who after the results show said that he was still in shock that his favorite singer didn’t win.

"Shin, I have to tell you, last night was the best he has been," Cowell said in an interview after the show. "I mean, his performance was magical — literally! And he’s a nice guy, but of course, my heart was with Michael."